/*
    * Copyright (C) 2008-2009, Google Inc.
    * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
    * Copyright (C) 2006-2008, Shawn O. Pearce <spearce@spearce.org> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
   * SPDX-License-Identifier: BSD-3-Clause
   */
  
  package org.eclipse.jgit.internal.storage.file;
  
  import java.io.IOException;
  import java.util.zip.CRC32;
  import java.util.zip.DataFormatException;
  import java.util.zip.Inflater;
  
  import org.eclipse.jgit.internal.storage.pack.PackOutputStream;
  
  /**
   * A {@link ByteWindow} with an underlying byte array for storage.
   */
  final class ByteArrayWindow extends ByteWindow {
  	private final byte[] array;
  
  	ByteArrayWindow(PackFile pack, long o, byte[] b) {
  		super(pack, o, b.length);
  		array = b;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	protected int copy(int p, byte[] b, int o, int n) {
  		n = Math.min(array.length - p, n);
  		System.arraycopy(array, p, b, o, n);
  		return n;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	protected int setInput(int pos, Inflater inf)
  			throws DataFormatException {
  		int n = array.length - pos;
  		inf.setInput(array, pos, n);
  		return n;
  	}
  
  	void crc32(CRC32 out, long pos, int cnt) {
  		out.update(array, (int) (pos - start), cnt);
  	}
  
  	@Override
  	void write(PackOutputStream out, long pos, int cnt)
  			throws IOException {
  		int ptr = (int) (pos - start);
  		out.write(array, ptr, cnt);
  	}
  
  	void check(Inflater inf, byte[] tmp, long pos, int cnt)
  			throws DataFormatException {
  		inf.setInput(array, (int) (pos - start), cnt);
  		while (inf.inflate(tmp, 0, tmp.length) > 0)
  			continue;
  	}
  }